Gasket



Patented Apr. 6, 1948 a GASKET ommeernzramlmmmngemmw.

.Applicationfictfiber 2, ISMgfSeiial-Nofifilijtli (cum-r20) .Thisinventiomreiatestofimprovements?inigasi'ketsarfd particularly to thatitypetofgga'sketused in bolted tanks .an'dfthe like.

"In the conventional construction of bolted tanks the overlapped edges of (the "tank "sheets have registering holes. spaced from each otherxm approximately? centers designedto receive the bolts. "Usually a shallow :ohannel "ironiis' posi- 'tioned against one. side of the lapped: sheets .and .the bolts are; inserted through the channel iron through the registeringholes an'dihavenutsrap- ,plied to the opposite sides. .Priorzto the attachim'ent of adjoining sheets the ,channeLTbolts and gasket are :1iustalled. 'Heretofore such gaskets 'haveibeen in the form of strips ;of"rubber .orcrdb- 'tber-likematerial, such as synthetiorubbenl'having undersized holesflpunched therein to permit of thelinsertion of the bolts therethrough. Genera'lly speaking, "thebo'lts used are and i 12 "in -diameter and'where"f%" bolts are'tobe .employedtheiholesithrough the gasket stripimayibe only l/fl'inidiameter. Wheretheboltsitolbelem- ,ployed are%"':boltsttheiholes .thr'ough the gasket strip are.zapproximately %".in fdiameter. "With gasket strip thus constructed -when "bolts .are tightenedthe material otlthe gasket immediately surroundingthe boltsis subjectlto very highhcomnression. This'high com re sioncausesithagas- 'ket to creep or flow radially awayfrom'ethearea immediately around the "bolts 'Lto' areas ;of .less compression such asthe space hetweenlthe'bfil'ts and outward "'frombetween the -lapped sheets. This flow of the rubber or rubber likelmaterial from the areal-immediately surroundingrthe-bolt tion of bolts therethrough, and Winch will "provide ran :adequate amount sof rubber in the immeiilate-"netghborhood of the bolts which" will not iiowtawaywhentsubjeoted'tocompression; but-will 'renrainin 'this locality-to be 'pressed firmly into engagement with the bolts, "suitable "provision being 'mejde'to prevent'prretard'anytendency of the gasketito flow.

another obiect of "the "linventionis "tc provide "anlimproved-ga'sketfforibolted rtanksandthelike "consisting -o! a 7812111) :of nibber or rubber like material having. spacedfiucalitieswhere "the bolts may-be I inserted tln'ouglfthe gasket, such localities having'slits -extenlziingihrwarrllyfromja circumferenceapproximateiy "equalto that o'ftthe i'boitdeflningaipim'alityof mutuallydndependent inwardly exteniling' flngers that are'readilybend- "able to enable -thetin'ser-tion "(if .the bolt, these "hngersbecomingiodged orwedgetint their i'nner ends ibetween itlrethrearls on Fthe :bolts and the walls of 'theholesiin hthe ilappe'd "sheets 'sothat r'theywill'rten'fl:tobefmeohanicaliy"held'in positi'on around the"*boltstoresistffiowing ofthe material ouwar'dly when the bolts are tightened and" the Zgasketthus isiibiectewtomigh compression.

"wan #the :foregoing andother: objects in view, which "will be :ma'tie :nranliest ;in the following "detailed "description "and specificallympolnte'd out the "appendeii claim; reference isihad .to the at:c'onnranyimg fdrawin'gs fionanillustrative em- '%botlimerit ao'f lfthe inventiomwherein:

Figure 1 i is :a sectional 'view through. a typical is apt to resulti-inleakageinlthatthe liquids c0n s Seam T iboltedit fi illlu m gasket tained 'in .the tank .may follow lthe bolt threads andlleak betweenthelthrea'ds ofuthe .bOltandithe material of 'thehgask'et.

If the holes in the ,gasket are "made much smaller so'thatl'they willhavea greatertundersize with relation tollthe bolts they' interfere .with the insertion of the bolts .therethrough and when 'the bolts-areliorcedt rough the gasket, the gasketis apt to tear resulting in leakage. In some forms of construction thezgasket is reenforced by having incorporated therein a reenforcing febr le-intended to-resist tearing Howeven-such fabric has sometimes been *criticizedin that *it functionsaszawvick 'andthusdntlucesfleakage.

It is highly desirable to have a gasket whiohis .so constructed that bolts maybe readilyrna'ssed "therethrough "but which will provide an excess :or "rubber -immediately around Lthe bolt so .'.that 'WhenthiS excess of rubberis subjected 'to'the high compressiomoccasioned;bythe tightening of theibolts that all thesrubber will not flowtatvay ,Irom'the sides of theibolts butlsufllcienttwill remain in 'this"'locality and be compressed against the sides of the bolts and the threads thereon.

An object of the invention is to provide an imbody'ing-oneffcrmnfthqpresent inventionashav- "ing been installed therein, the bolt being indi- .catedin *a posit'i'on flustprior' to tightening;

rri ggwisamartialviewf in elevation' of. a section "of "one *form of iigasket embodying "the "present "invention: l a

'"FigsJB, 4,-antlf5are similar views illustrating "alternative forms of construction of gasket embodying the present invention; and

'6 is .a sectional view itaken substantially *uponifhe'ilineili tnponiFigfB. i

Referring to the accompanying drawings wherein "similar reference .h'araeters designate t's'hniiargrpartsthroughout, .111 and ill! indicate .tivo 'sheets o'fta'bolteiiltank .havinglapped edge .-.p.oritionsin-which there .arelregistrable .holes .12 and LI 3 designed ltoireoelvebolts II on which arerapgnlieable :nuts Illa In conformity with general practice :a .h'annl L'iron 1T1 Jis positioned; between the"head iof ithe bolts I13 and the .sheet Ll. I Qne itorm er gasket embodying "the presentlinvention this .as illlustra'te'd -in Tlig. 3, sconsis't'ing of .a strip .18 rof sui't'able widthan'dnf alengthadequate to extend the entirelength of the seamiin which there are spaced localities providing for the inpermit of the easy insertion of the bolts Hi there-.-

through. These fingers tend to bend outwardly sympathetically with the movement'of the bolt 4 In Figs. 5 and 6 still a further alternative form of construction is disclosed. In this form of construction there is a strip 30 formed of rubber or rubber-like material in whichfthere' are ex- 'tremely small apertures 3|. Surrounding these apertures the thickness of the gasket may be considerably reduced, the reduction in thickness being apparent in the form of concavities 32 surrounding the apertures. Radial slits 33 may ex- ..t'end outwardly from the apertures 32 defining fingers 34 which, because of their reduced thick- 1 ness, are extremely flexible. These thinned finand their inner ends become lodged or wedged between the threads of the bolt and the walls of the holes in sheet l0. In this form of construction, inasmuch as no portion of thestrip neighborhood of the bolt in a radial direction when subjected to a high compression. When this excess of rubber is thus compressed, it then tends to remain immediately surrounding the bolt and will be crowded inwardly into firm engagement with the threads thus affording a leakproof joint around the bolt.

In some instances, the nature of the rubber or rubber-like material or itsthickness is 'suchthat it may be desirable to reduce the amount of this excess of rubber, immediately surrounding the .bolt. In such instances,'the gasket may be constructed as illustrated in'Fig. 3, wherein it consists merely of a strip of rubber or rubber-like material 2| with spaced openings 22 formed therein somewhat in the nature of star-shaped openings. These-openings are formed by cutting or punching-out portionsof the rubber strip in the form of widened slits 23 defining relatively shallow fingers 24. The'slits 23 have their outer. .ends around on a circumference approximately equal to that of the bolt and the bases of the fingers 24 are likewise arranged approximately on a circumference equal to that of the bolt. In using this form of construction the bolt may be readily inserted through the openings as the fingers .24 are readily bendable and an excess of rubber is retained in the immediate neighborhood of the bolt for the purposes as above described. In this form of construction the excess of rubber present is not as great as that present in the construction as illustrated in .Fig. 2, but is nevertheless adequate to form a leakproof seal around the bolt.

Fig. 4 illustrates another form of construction wherein the strip 25 has a materially undersized aperture 26 punched therein. Thus the diameter of this aperture may be one-half the diameter of the bolt or even smaller. Extending outwardly therefrom are pre-formed radial slits. 21 defining fingers 28. These slits terminate on a circumference approximately that of the bolt. In this form of construction the bolts may be readily inserted through the gasket and the fingers 28 bent laterally. In this former construction also there is not quite the excess of rubber present around the bolt as in the case of Fig. 2. By increasing or decreasing the size of aperture 26 the amount of excess rubber. around the bolt may .regulaitgdr. Y

gers may be employed in situations where the clearance between the bolt hole and the bolt is quite small. In some instances. it is possible to omit the radial slits 33 in this form of construction entirely in which case the bolt may beforced through the gasket and the thinned material around the apertures 3| will have sufficient stretchto enable thev bolt to be passedtherethrough with the material of the gasket stretching about it. In this form of construction the amount of excess rubber left in close proximity to the bolt can be regulated by increasing or decreasing the size of the apertures 3| 'orthe depth of the'eoncavities32'." 1 I From the above-described constructions it will be appreciated that an improved gasket for bolted tanks and the like is provided which enables the bolts to be readily. extended therethro'ugh, An adequate amount of therg'asket material is .left

in close proximity to the bolt so that when the bolt is tightened the gasket. material will {not be crowded or caused to flow aWayLfrorn'Inasmuch as the slits are pre-formed in;the-. gasket material and the, fingers definedfthereby are quite flexible and readily bendable danger of'the gasket splitting due .to forcing {a bolt through'an undersized aperture is eliminated. While reenforcing fabric may be incorporated in .the rubber of the gasket strip, such reenf orcin'g ,fabric is unnecessary and is usually left out to avoid wick action. a y

Various changes maybe made inthe details of construction without departing from thejspirit and scope of, the invention as defined by the appendedclaim. H H y r I claim: f f A gasket for bolted tanks and thelike comprising a strip .of rubber or rubber-like; material having spaced openings therein adapted tlo i'eceive bolts, said openings beingmaterially' smaller in diameter than the diameter of theboltsandhaving pre-formed slits extendingoutwardly therefrom defining aplurality of mutually independent fingers, the thickness. of the rubber being decreased in the area surrounding said openings.

. CLARENCE ,1). ,LAIDLEY.

' E EREN E I I E The following references are of record in the file ofthis patent:

. 'v l 'e eefeArms j Number I Great Britain :1935 

